Wincor Nixdorf iPOS plus Advanced, User Manual

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Resistive Touch Screen
01900xxxxx iPOS plus Advanced – User Manual 23
Resistive Touch Screen
General Information
The resistive TFT Touch Screen is constructed by a hard-coated
polyester top sheet that is overlaid on a conductively coated glass layer.
Voltage is applied to the top sheet. As the user touches the screen, the
top sheet compresses into contact with the glass layer, and current flows
to the four corners in proportion to the distance from the edge. The
controller then calculates the position of the finger or stylus, based on
the current flow. Because the controller derives both the “X” and “Y”
touch coordinates from the stable glass layer, the accuracy and
operation of the touch screen is unaffected by damage to the top sheet
caused by extended use or neglect.
Construction of the Resistive Touch Screen